Electric sign.



PATENTED JUNE 9, 1903.

H. B. WRBN;

ELECTRIC SIGN..

APPLIQATION YILED JUNE 7, 1902.

N0 MODEL,

TnE wonms Pnzas cc. mom-uma. WASHINGTON, u. c.

NO. 730,854. 7 I Patented June 9, UNITED STATES PATENT OFFICE.

HARRY B. WREN, OF l/VASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR OFTHIRTEEN-FORTIETHS TO JOHN I. CASSEDY, OF FOREST GLEN, MARY- -LAND, ANDWALTER R. HENSEY'AND M. LE ROY GOUGH, OF \VASHING- TON, DISTRICT OFCOLUMBIA.

ELECTRIC SIGN.

SPECIFICATION forming part of Letters Patent No. 730,854, dated June 9,1903, Application filed June 7, 1902. Serial No. 110,612. (No model.)

To all whom it may concern: invention the conducting material of theele- Be it known that I, HARRY B. I/VREN, a citiments may be substitutedby electromagnets, zen oftheUnited States, residing at Washingwhich mayattract metallic filings of various ton, in the District of Columbia,have inventcolors and produce the outline of the letter 5 ed certain newand useful Improvements in or character desired.

Electric Signs, of which the following is a In the accompanyingdrawings, Figure 1 is specification, reference being bad therein to aface elevation of one monogram, showing the accompanying drawings. thearrangement of the elements. Fig. 2 is Thisinveution has relation toelectric signs; a rear view of one monogram, showing the to and itconsists in the novel construction and electrical connections betweenthe various arrangement of its parts, as hereinafter deelements; andFig. 3 is a transverse sectional scribed. view of one of the monogramscut on the line The objectiof the invention is to provide a 3 3 of Fig.1.

sign adapted to be electrically operated, said I do not make claim tothe arrangement of I5 sign consisting of a single monogram or deelementsnor to the electrical connections for sign or a series of mouograms ordesigns. the same, and I do not confine myself to the Each monogram ofthe sign or signal appara particular arrangement of elements as showntus is composed of a plurality of elements of in the drawings, myinvention residing prinsuitable form, such that by dilferentiatingcipally in the construction of the monogram 2o predetermined groups orseries of elements or sign and the substance of which they are lettersof the alphabet, numerals, or other composed. characters mayberepresented, said elements The monogram or sign consists of afoundabeing composed of suitable conducting matetion 1, made of suitablenon-conducting ma- 7o rials coated or permeated with or composed terial,in which the conducting elements 2 2 25 of a chemical or chemicalcompound that are embeded, each element being electrically changes colorwith change of temperature or connected by means of suitable wires 3.The other change of state, said monogram or outline of theelemeuts maybe such as shown monogram-sign being adapted for use in comin Figs. 1and 2 of the monograms. By rebination with a suitable switchboard mech-'ferring to Fig. 3 it will be seen that each ele- 30 anism,(not shown,)whereby any design or ment 2 is insulated from the other elements anyelement or predetermined series of eleby means of the material 1, andthe exposed ments of a monogram and successively of a faces of theelements 2 are covered or perplurality of similar monograms may bemeated with or composed of a chemical or charged at will with anelectric current from chemical compound 5, which changes color 35 asuitable generator, said current or charge with change of temperature orother change being adapted to produce in the material of of state. Thechemical compound 5 above said elements or the chemical constituentsreferred to may consist of ingredients put tothereof change in color,and thereby to progether as follows: a mixture of one part of ducegraphically at will any desired numerpowdered cobalt and four parts ofaqua regia,

4o als or characters, choice being made of any add one part of sodiumchlorid and sixteen suitable substance or combination of subparts ofwater, filter, and mix with gum to stances that possesses the propertyof repeatthe consistency of paint. The electric cured cyclic change ofcolor with change of elecrent is .passed over the wires 3 3 to the eleotrio, physical, or chemical state, which change ment 2, the temperature,electrical, physical,

45 of state is produced directly or indirectly by or chemical state ofwhich is instantly local electric action. changed. Thus changing thetemperature or Without departing from the spirit of my other statechanges the color of the elements or coating 2. of the particularelements charged, and thus the outline of the letter or character isproduced in color different from that of the element or coating atnormal temperature.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is-

1. A sign consisting of a foundation of nonconducting material, a seriesof plates or elements insulated from each other mounted on saidfoundation, each adapted to be independently electrically connected andpresenting a chemically-prepared surface,adapted to change color withthe change of temperature or other change of state.

2. A sign consisting of a series of chemically-prepared plates orelements suitably mounted and separately insulated, a means for changingthe temperature of said plates or elements, said elements adapted tochange color with change of temperature.

ture changed.

4. A sign whereby letters and characters may be produced at will,consisting ofa chemically-prepared surface and a means for applying anelectric current locally to said surface to produce a change of color.

In testimony whereof I afiix my signature in the presence of twowitnesses.

HARRY B. WREN.

Witnesses:

CHARLES F. HATCH, ANNA E. STULL.

